Are the lesions of duct ectasia sterile?

A prospective study was established to determine whether, using suitable transport media, bacteria could be isolated from the lesions of mammary duct ectasia. The results indicate that both aerobic and anaerobic organisms are present in a high proportion of patients with nipple discharge associated with this condition and in all patients who develop peri-areolar sepsis (abscess and mammillary fistulae) as part of the syndrome. The lesions of duct ectasia are therefore not sterile and the possibility exists that bacteria have a role in the aetiology and pathogenesis of this condition.